How we tested
It’s early March, and a team of our editors is driving along a winding dirt road in Vermont to visit a sugar shack tucked against a mountain covered with thousands of maples. At first glance, the passing forest scape is a canvas of barren trees and snowy fields, but a closer look brings into focus a web of silver taps and clear plastic tubing weaving among the trees—the sign that it’s sugaring season.
We’ve timed our trip carefully because sugaring season is both short and temperamental. Not only is the majority of the world’s maple syrup produced on relatively small-scale farms, like this one, throughout Canada and the northern United States over a period of just two months each year, but the sap production is entirely weather-dependent: Syrup makers must wait for freezing nights that are followed by warm days, a pattern that causes higher pressure within the tree to push sap out of the tree. Couple that with the fact that it takes 40 gallons of sap to produce just 1 gallon of maple syrup and it’s not surprising that this product can fetch more than $1.50 per ounce.
Anyone who’s tasted real maple syrup on pancakes, in desserts, or even in savory glazes or dressings knows that there is no cheap substitute. We confirmed as much a few years ago when we compared a few maple syrups with pancake syrups; the latter, corn syrup–based products that are a fifth of maple syrup’s price, tasted cloying and candy-like. This time, we decided to home in on pure maple syrup and gathered eight products, all Grade A Dark Amber since it’s the most widely available grade, tasting them plain and baked into maple syrup pie.
From Sap to Syrup
Pure maple syrup is simply sap from sugar maple trees that has been boiled to concentrate its sugar. To harvest it, taps connected to plastic tubing are drilled into the trees; the sap flows through the tubing into large storage containers where it’s held for no more than 24 hours (unprocessed sap is only about 2 to 3 percent sugar, so it spoils quickly). When it’s time to boil, the sap is transferred to an evaporator pan set over a large fire and reduced until it reaches 66 percent sugar density. (If it’s boiled much longer, the syrup will start to crystallize; any less and it will eventually spoil.)
After the sap has been boiled and filtered, it’s graded according to color, which also helps categorize the strength of its flavor. David Lutz, a forest ecologist at Dartmouth College, explained that syrup color and flavor are primarily determined by changes in the chemical composition of the sap throughout the sugaring season. At the start of the season, the syrup is very light-colored because the sap is infused with stored sucrose from the winter and generally free from compounds that impart strong flavors or a dark color. (The earliest, clearest sap was historically graded “A, extra fancy” because it was the best representation of a neutral-tasting sugar substitute.) As the season progresses, the environment becomes more biologically active, the tree prepares to bloom, and hundreds of phenolic compounds—the same types of chemicals found in tea and wine—start flowing through the sap, darkening its color and deepening its flavor.
Although Vermont and some other states have their own grading systems, there are no universal grading standards in the syrup industry. But there are five main grades that range from Grade A Light Amber to Commercial—the latter a syrup so strong-tasting that it’s reserved for industrial use. To assess color and assign a grade, some syrup producers use a spectrometer, a tool that measures the amount of light transmitted through the syrup, but more often grading is low-tech and subjective: Syrup makers simply compare their finished syrup to color charts or small vials of dyed glycerin. If the syrup falls between two hues, producers often choose the darker grade because syrup may darken with time due to oxidation. (Note: The U.S. Department of Agriculture and a handful of syrup-producing states will be issuing new grading conventions for maple syrup effective in 2017.) Perhaps because grading is such an imprecise process, we noticed some color differences among the syrups in our testing, even though they were all labeled the same Grade A Dark Amber. Some were dark like molasses, while others were only faintly golden—but surprisingly these color differences did not correlate to the syrups’ flavors. Most of the lighter-colored products tasted just as robust as darker ones. In fact, we were hard-pressed to find any distinct differences among the syrups other than color. Ultimately, we recommend them all.
Still, we were curious about the discrepancy between syrup color and flavor and turned to Michael Farrell, director of Cornell’s Sugar Maple Research & Extension Field Station, Uihlein Forest, for an explanation. He noted that unless you’re comparing the very lightest grade with the darkest one, the differences in flavor can be pretty subtle. More significantly, he added, the distinct flavors in maple syrup have been literally blended out of most supermarket brands. Because each maple tree averages only 1/4 gallon of maple syrup over the entire season, it’s impossible for most producers to acquire the land or resources necessary to yield enough volume for national distribution. Instead, most producers sell their syrup to large packagers, which pool hundreds of different products and bottle the blends under a brand name. Farrell and other experts told us that to get the color and flavor profile that falls within the Grade A Dark Amber spectrum, the most marketable grade of syrup, they blend different grades. “If their Dark Amber is looking a little too dark, they might mix in medium to lighten it up,” Farrell said. The goal is “to try to make a consistent product.”
Some packagers might even doctor the syrups with cheaper sweeteners to maximize their yield, but Farrell doesn’t feel that it’s a major issue in the industry. His bigger concern is pancake syrups masquerading as pure maple syrup, either from packaging that makes pancake syrup look like the real thing or from the inclusion of a small amount of pure maple syrup. “It changes people’s opinions of real maple syrup,” he said.
To us, there’s a distinct advantage to blending: It means that all Grade A Dark Amber syrups sold in supermarkets are going to taste very similar, so our advice is to buy the cheapest all-maple product you can find.
How Nature Colors Syrup
The color of maple syrup ranges dramatically over the course of the two-month sugaring season due to natural chemical changes in the sap. As the tree becomes more biologically active, phenolic compounds develop that infuse the sap, imparting color (and flavor). First-of-the-season sap is almost clear because it contains few of these compounds. As the season progresses and the tree prepares to bloom, more compounds deepen the color of the sap.
EARLY SEASON, PALE SYRUP: Few phenolic compounds
LATE SEASON, DARK SYRUP: Many phenolic compounds
Single-Origin Syrups: Worth the Splurge?
While most maple syrup producers sell their products to large packagers who blend and sell them commercially, there are also some who sell their own unblended syrups directly from their farms (or through local specialty stores). Curious if these single-origin syrups would have more distinct, nuanced flavors—and if they would be worth mail-ordering—we tasted five (priced from $0.48 to $1.33 per ounce) alongside one of the supermarket brands. We liked them all, but none had distinct enough nuances to warrant the shipping charges—a result that maple syrup expert Michael Farrell said isn’t surprising. “Most people,” he noted, “aren’t going to be able to tell the difference.”
Twenty-one America’s Test Kitchen staffers sampled eight nationally available supermarket brands of Grade A Dark Amber maple syrup in two blind tastings—plain and in maple syrup pie—and rated them on flavor, sweetness, and strength of maple flavor. We obtained information about processing methods from manufacturers and industry experts. Because we found all the syrups to be very similar and recommend them all, we don’t have a favorite; instead, they appear in order of price per fluid ounce.